1. Field of the Invention
This invention relates generally to hand tools, and more particularly to hand tools for applying pressure to a work piece. In even more particular aspects, this invention relates to squeeze action hand tools which will generate a given reaction responsive to a predetermined force being applied to a work piece and is especially adapted for use in crimping type operations.
2. Background Art
Crimping and other force applying tools are well known in the art. These tools are used to apply a limited force to a work piece, such as crimping terminals to wire ends or applying other types of fittings or harnesses to wires, or wire bundles. Typically these tools provided a jaw action that is limited after a predetermined amount of travel, or within a given distance of full closure. However, one tool, described in U.S. Pat. No. 4,640,117, is configured to react after a predetermined amount of force has been applied rather than at a given distance of travel or degree of closure. This tool has a very good force limiting feature, but the jaw action is rather complex, requiring relatively complex and expensive jaw parts. This jaw design also requires a great deal of precision in parts construction to maintain a proper plane of travel of the moving jaw to thereby assure that the jaw remain parallel during the squeezing action. The necessity of the jaws to remain parallel is especially important when the work piece being squeezed is relatively wide and/or long, and the force must be essentially uniform over the entire surface. Further, and of great significance, is that the force multiplication at the jaws of this design is a linear function of the force applied to the handles. Thus, the force that can be applied to the work piece is limited to the amount of force that can be applied to the handles over their path of travel. Expressed another way, the force applied by the jaws is a contrast multiple of the force applied to the handles. Thus the amount of force available is limited by the handle configuration.